


Lifetimes and Heartlines

by It_MightBe_Love



Category: Avatar: The Last Airbender, Supernatural
Genre: Crossover, Crossover Pairings, M/M
Language: English
Status: Completed
Published: 2012-03-27
Updated: 2012-03-27
Packaged: 2017-11-02 14:29:37
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,232
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/370023
Author URL: https://archiveofourown.org/users/It_MightBe_Love/pseuds/It_MightBe_Love
Summary: <blockquote class="userstuff">
              <p>In another life Aang was sure he'd have found this situation funny, nowadays it just breaks his heart.</p>
            </blockquote>





	Lifetimes and Heartlines

Aang has spent a lifetime coming to terms with the fact that he remembers everything. He woke up this lifetime and there was this beautiful doorway in his mind that he had wanted to crawl through and so he head and then their they were. All these memories and ideas and realities he hadn't previously known existed.

He's read books about people who wake up aware of existence too young. Hell, he's pretty sure one of the chief reasons Frank Herbert's Dune novel's were so popular was because of that key concept almost entirely. The point is, his life sucks sometimes.

He's born to a middle class white family, his parents divorce by the time he's fourteen and instead of picking between them in what turns out to be a really terrible, drawn out divorce, he asks the judge to send him to Texas to live with his great aunt. She's kind of a kooky old lady who always smells like patchouli and she wears a ton of crystals.

She never questions how he knows things sometimes before it's possible to have learned them properly and in thanks he does something he hasn't done in several lifetimes. He talks about reincarnation and past lives. His Great Aunt is a bright spot on a lifetime where every morning that he wakes up his heart shatters into a million pieces.

He goes to university young and decides that anthropology interests him. He's good with history and eventually he amasses a collection of literature that sometimes has people's eyebrows raising.

Aang knows things about the Christian God though that would have more than eyebrows raising though and he figures if all else fails that at least he'll be useful when the shit hits the fan. Which is why he is both expecting the knock at his office door one day a few years into his tenure-ship and isn't.

Isn't because coming face to face with Dean Winchester who is the spiritual spitting image of Zuko is like someone out there pointing a finger and laughing at him. It feels like he's stepped into one of those tragic romantic comedies. The one where the nice guy doesn't end up with the girl (or guy) or his dreams. Instead he stands back and watches her(him) ride off into the sunset with someone whose eyes are the color of a summer storm. (Aang doesn't know this yet, at the time he can't think past the frantic beating of his heart and the way Dean's smile soothes every ache in his chest like they didn't even exist).

"Ain't you kinda young to be a professor?" He asks roughly and something down by his leg fidgets. Legitimately -fidgets- and Aang's eyes (brown this lifetime) are drawn down to a head of curly wheat blond hair and the biggest, greenest eyes he's seen in his life.

"I finished high school very young. I promise, I'm quite good. You're here about the manticore in the sewers I'm assuming?" Aang asked, before letting Dean and the little girl into his office and shutting the door.

from the expression on Dean's face he hadn't been expecting - "You know about that?"

"I'm the one who contacted you. Of course I know about it." He rolled his eyes and there was that same dumbfounded smugness around Dean's eyes and mouth that made Aang think of Zuko.

"There isn't actually a lot of lore on manticore." he told Dean, going to his desk and rooting through the piles of papers before finding the small, cloth bound book he'd been reading and flicking it open.

"You're supposed to cut off it's head." He said, which sounded easy enough.

Dean nodded, "Easy enough."

"With a sword consecrated by magic." Aang wanted to role his eyes, this was the problem he thought- with the fall of the pagan gods and the rise of the Christian one. They left their toys out for people to trip over. It irritated the hell out of him - "It has to be silver."

Dean frowned, "The silver should be easy enough, but magic's kinda hard to come by these days and-"

"I have one. Well, it was blessed by a saint but it's real enough. It should do the job but you can't let the manticore claw you. You'll be cursed to become one if it's claws draw blood." Really nasty toys. He wondered if the old Gods had meetings about ways to make people's lives difficult.

He doesn't say that the sword was Zuko's. That he'd sobbed when he'd come across it, had never told anyone why he'd spirited it away the way he had.

Dean's mouth puckered in a frown so reminiscent of someone else Aang saw double for a minute, "Well... that's both convenient and a pain in the ass." he grumbled.

Aang snorted, "If it weren't you wouldn't be convinced it was real." he said, too knowing and the look Dean gave him was questioning and interested.

His cheeks and ears flushed under the intensity of that scrutinizing gaze before he cleared his throat and handed Dean the book, "I keep the sword in a safe at my house unfortunately and I have a lecture to give. My address is on the inside label. Feel free to come pick it up this afternoon after three."

Dean opened his mouth to protest but Aang was hurriedly collecting his things and fleeing before he did something stupid.

Here's the thing- before the rise of the Christian god the Earth was inhabited by people, a different sort of people, but people nonetheless and the Gods were spirits who controlled without controlling. Who loved their people, and who loved them well enough that they would often die for them.  
They gave their people Heartlines. Soulmates in the modern tongue and in the middle of a war that Aang had been too young to understand, he had found his in the form of an exiled Fire Prince named Zuko.

He'd shared a lifetime protecting that Heartline, and when he'd awoken in the next curious at the memories lingering at the periphery of his mind he'd been stunned to realize that the war they had been fighting had been lost on a cosmic scale. Apparently the old Gods were also pretty terrible at poker, before upper management changed and so did the surface of the planet and before Aang knew it new peoples were suddenly there in existence and Angel's were swooping down in these swirling balls of light and sound. All fury and terror and heartache and love - Aang hid.

He hid because that was what he had gone down in history as- the coward. The man who slept for a hundred years and all but destroyed his people. No matter that he had saved everyone in the end a coward was always a coward no matter how brave they were in the end.

Modernity suits Aang pretty well though. he likes his coffee maker and his car. He loves reality television and the food network to a degree that horrifies some of his coworkers. He spends some of his summers volunteering in other countries, rebuilding or giving out food or vaccines. Sometimes he spends entire summers on his couch, his heart breaking.

But he lives, he doesn't let himself hide because it hasn't gotten him anywhere but the year 2012.

Dean shows up on his doorstep, little girl in tow and he finds himself with an armful of what he's estimating to be four year old with sticky fingers. "You said you kept it locked up in a safe? Another man's gone missing."

Aang slides the girl to his hip and leads Dean into his office, "Combo is 1-24-79." he told him.

Dean started laughing and the girl giggled brightly, "What?"

"Nothin'. Your combo is my birthday is all." He said and Aang had to repress the urge to say 'I know' or 'That is your birthday every time you're reborn' or ask why they chose this lifetime of all lifetimes to bring him back into his life when he clearly belonged to another.

"Interesting."Aang swallowed and found himself hugging the girl a little tighter.

"So Professor, you got a first name? Since you know mine already." Dean asked, opening the safe and investigating.

"Aaron. Aaron Fremont. Well I mean you knew my last name already. it was on my door. But it's Aaron." Aang felt like an idiot.

Dean nodded, "Well you're holding Olivia and since you already know me I guess that means introductions are done an' over." He found the sword, tucked in the back behind several scrolls filled with writing that made his fingertips tingle with knowledge and hefted it.

"Well at least you don't have it stuck in a god damn rock." He muttered.

"Excuse me?"

"Oh, nothin'. Don't worry about it. Look... would you mind keeping an eye on her for me? This shouldn't take too long but usually my brother's here. I sent him on a little vacation. He's been having a rough time of it recently." Dean said, mouth twisting in a frown that was growing more familiar by the minute.

Aang shook his head, "No... it isn't a problem. Should you really go alone though?"

Dean lifted a shoulder, "Can't be any harder than taking down a wendigo."

He left and Aang spent the next several hours entertaining a four year old.

It became habit - for Dean to call him up. Eventually Sam as well. or they'd drop by and Aang would spend hours entertaining Olivia who he was quickly learning to love fiercely. For her father's green eyes and the quicksilver laugh that meant she was causing trouble.

He slept with Dean on those nights and weeks. Lips fierce and unrepentant, aching and desperate and totally aware of how utterly messed up the entire situation was. He'd pull sighs out of Dean's chest with practiced fingers, and let broad hands guide him onto his stomach and open his body up.

It was on these nights he learned about the blue eyed Angel Castiel, and it filled him with a vicious jealousy he hadn't expected to experience. He knew of ways to fix it. Gods above he did but he wanted just once to have something that was his.

"How did you come to have a small child anyway?" Aang asked, brave one night with sweat and other things still cooling on his skin. Dean hummed noncommittally and brushed his mouth over the curve of Aang's shoulder.

"Knew her mom a couple years ago. Met up with her about... of seven months ago. She was having some problems with ghouls - couldn't handle'em herself and by the time we;d got there she was already dead. I'm listed on the birth certificate so it wasn't like anyone could stop me from keeping 'livia but..." Dean went quiet.

This was another difference between Dean and his Zuko - there was so much... well Aang had no doubt that had Zuko been raised the way a Prince should have been he would have wound up much the same way Dean obviously had, hunting supernatural creatures notwithstanding.

"And now you find yourself in possession of a small child on the road?" He said, not asking what Dean would do when it was time for Olivia to start school, or how he would handle raising a teenage girl on the road. How he would protect her. If it was fair to subject her to that kind of life.

Knowing Zuko, and knowing Dean. These were already questions he was struggling with. Dean laughed, "Yeah... it's pretty crazy but I love her." He said, let the sharp edge of his teeth scrape distractingly across Aang's pulse.

He let himself be distracted.

It settled into routine until he stumbled on the scroll, and left it sitting out for Dean.

"What is this?" He asked, eying the dusty parchment warily, picking it up and reading over it quietly. In some language he would never have heard of because the people who had written it had not existed since before the old Gods had fallen.

"It's the scroll that'll fix your friend Castiel." Aang said, head inside the refrigerator while he pretended to be looking for the mayonnaise.

"The... Aaron-" Dean said, voice rough and Aang pulled his head out of the fridge to level his best Airbender stare on Dean. It was still surprisingly effective even with a hundred lifetimes of time between them.

"I know how you feel about the man Dean. It's... I'm not going to lie and say it's all right, because it really isn't. But I know what it's like to live without the piece of your heart that makes it whole. I've had... a long time to learn how to deal with it. You haven't."

Zuko had been his Heartline, but he'd never been Zuko's. A cosmic flub that they had, once upon a time learned to live. Nowadays though just talking about Castiel made Dean's face light up. Aang knew that look, that was how Zuko had used to look at him.

He cleared his throat, "It'll heal him. Should I ought to say... I'm not well versed on Angel biology but it should work." He found the mayonaise and set it on the counter, before Dean was crowding him up against it and kissing him, fingers tucked beneath the curve of his skull, mouth fierce and forgiving on his.

"You are... you don't have any idea what this means to me." Dean managed, voice catching like he was choking on marbles. Aang did know, he knew exactly what this meant to Dean, and what it would mean for him, but he took another kiss and shoved him away.

"Let me make my sandwich. I have grading to do. Figure out the spell and when you're leaving." He said, and refused to let his voice break because if it did, everything else would break all at once.

Dean's fingers tightened on Aang's hip, "Aaron... I-" There was that guilt creeping into his voice and Aang blew out a breath.

"Dean, seriously... we're happy but you won't ever be completely happy without him. He's yours isn't he?" This was exactly the kind of talk Dean hated having. All emotions out in the open and confessing to things that had no right to be confessed. Aang knew because Zuko had been the same way. Declarations of love had been like pulling teeth.

Dean nodded, "Yeah. He's mine." He said, voice leaving no room for argument, "But you're - "

"No buts. You've given me a lot. Now let me give you this. As bullshit as that line about being happy knowing your loved ones are happy is... it's also true. So take this happiness I'm trying to give you and stop being a dick." He pushed him away again and dug a butter knife out of the dishwasher.

Dean nodded and Aang listened to him leave the kitchen before dropping his head to the counter on his forearms.

He was packing Olivia into her car seat the next morning, Dean standing in the doorway separating the kitchen from the garage, Sam a hulking presence behind him (screaming Sokka and how was that the funniest thing ever) - "Are you sure she'd going to be fine?" He asked, voice tight with worry.

Olivia had a scrape on one knee and without thinking, Aang dropped a kiss to it, doing something he hadn't done in a dozen lifetimes and healing it in a soft pulse of blue light. Olivia squealed happily, hands clapping, "Papapapapa." Chanted over and over again in that mercurial voice.

He straightened from the car, "Dean. It's preschool, she's going to love it; but she can't miss her first day and you're going on a trip. It'll be fine we'll see you in a few days." He smiled as reassuringly as he could and he must have gotten much better at lying over the last few lifetimes because it felt believable on his tongue.

He caught Dean in a quick embrace, ignored the distressed noises Sam was making before he climbed into his car and backed out of the garage. It was the last time he saw Dean.

Several months later was the first time he met Castiel, he had finished putting Olivia to bed, and he never knew what was worse, that Dean trusted him enough to keep his daughter safe, or that Dean couldn't stand to come back for her.

He turned and there was a man in his doorway and Aang bit back a shriek.

"You are not human." He said and his voice was like whiskey on gravel and Aang understood why this man affected Dean so.

He shrugged, "Not entirely. Neither are you though." He sidled around Castiel and shut Olivia's bedroom door, "You come to make sure I haven't eaten her?"

"How does Dean not know that you are not human?" Castiel asked, eyes narrowed suspiciously.

"Because I'm as good as. Consider me a precursor to Christian humanity." Aang muttered, wandering downstairs to the kitchen for a drink. He listened to the light tread of Castiel behind him. It was weird knowing Angel's had footsteps. He'd never met one fleshed before, another thing to add to is lifetimes list of weirdness and heartache. Katara would have loved knowing Angel's could have footsteps.

"You are from Before?" Castiel asked, leaning against the counter in a pose so mockingly human it gave Aang pause.

"Yeah, I'm from Before." He said, found the whiskey and poured himself a small glass, wondered if Dean actually had conversations with this not quite man and if they were as infuriating as he was guessing this one was going to be.

"How do you remember? I do recall the stipulation being that -" Aang waved a hand to interrupt him.

"Color me special. I don't know how or why I remember, but I do and Dean doesn't know because I know Dean. Knew Dean... from Before. He was... he was someone else and I don't want him to know. The same way you don't want him to know because it's messed up and messy and nobody needs to know." He said quickly.

Castiel's edges softened, it was such a visible change it left Aang blinking curiously, "He... wishes to know how Olivia is doing." Castiel said, apropos of nothing and Aang snorted into his glass.

"Tell him she's the bumblebee in the school play and misses him. Tell him you're all still welcome here. Tell him... " Aang sucked in a painful breath, "Tell him she's safe." He said and watched Castiel nod and disappear.

He finished the glass and left it in the sink, before going upstairs and curing up in the center of his bed. Castiel had eyes the color of a summer storm. The same shade as the blue his avatar markings glowed when he did anything out of the ordinary. It was ironic in a deeply unpleasant way, knowing that even in this lifetime Dean(Zuko) was a sucker for that shade of blue.

But he was happy and in love and Aang could live with that. Olivia had the same green eyes Dean did - the same quicksilver laugh and heave-ho attitude. He could learn to live without again. He had before but maybe this time it would get easier.

**Author's Note:**

> I seriously, sincerely have no idea how I came to write this. I know almost nothing about the Avatar fandom except that the few episodes I watched I wanted Aang and Zuko to declare their undying love for eachother. Obviously this translated into Supernatural somehow.
> 
> And yes, this was legitimately a dream I had last night, woke up this morning and immediately wrote. My brain is the strangest place to live. Ever.


End file.
